Axle assembly for a vehicle

ABSTRACT

Axle assembly includes first and second axle housings extending toward opposing sides of a vehicle frame with the axle housings aligned to define an axle axis, first and second wheel ends, first and second drive shafts disposed within the first and second axle housings, a gearbox having a first surface facing one side of the vehicle frame and a second surface facing the other side of the vehicle frame with the gearbox cantilevered outwardly relative to the aligned axle housings to define a gearbox axis parallel to a longitudinal axis of the vehicle frame and transverse to the axle axis, and an electric motor coupled to the second surface of the gearbox and extending toward the first side of the vehicle frame to define a motor axis that is parallel to and offset from the axle axis, transverse to the gearbox axis, and transverse to the longitudinal axis.

CROSS REFERENCE TO RELATED APPLICATIONS

The subject patent application is the National Stage of InternationalPatent Application No. PCT/US2016/067136, filed on Dec. 16, 2016, whichclaims priority to and all of the advantages of U.S. ProvisionalApplication No. 62/268,852, filed on Dec. 17, 2015, and U.S. ProvisionalApplication No. 62/333,032, filed on May 6, 2016. The contents ofApplication Nos. PCT/US2016/067136, 62/268,852, and 62/333,032 areincorporated herein by reference in their entirety.

FIELD OF THE DISCLOSURE

The present disclosure relates generally to vehicle axles and, moreparticularly, to an axle assembly for a vehicle.

BACKGROUND

Axles are commonly used in vehicles having wheels, such as passengercars and/or trucks, mass transit vehicles such as city and/or commercialbuses, agricultural vehicles, semi-trucks, trailers, and/or the like.Electric axles, i.e., axles having an electric motor, are increasing inpopularity. However, given the limited amount of space under the vehiclefloor, suitable and effective attachment of the electric motor to theaxle has become a challenge. The present disclosure is aimed at solvingthe challenge identified above.

SUMMARY

In one embodiment of the present disclosure, a vehicle comprises: avehicle frame having front and rear ends and opposing first and secondsides; a floor coupled to the vehicle frame and extending between thefront and rear ends to define a longitudinal axis adapted to extendalong a length of the vehicle, and the floor further extending at leastbetween the first and second sides to define a width-wise axis adaptedto extend along a width of the vehicle; a first axle housing and asecond axle housing each having first and second housing ends with thefirst housing end of the first axle housing extending toward the firstside of the vehicle frame and the first housing end of the second axlehousing extending toward the second side of the vehicle frame, and thefirst and second axle housings being aligned to define an axle axisparallel to the width-wise axis; a first wheel end coupled to the firsthousing end of the first axle housing adjacent the first side of thevehicle frame, a second wheel end coupled to the first housing end ofthe second axle housing adjacent the second side of the vehicle frame; afirst drive shaft at least partially disposed within the first axlehousing and coupled to the first wheel end; a second drive shaft atleast partially disposed within the second axle housing and coupled tothe second wheel end; a gearbox having a body with the body having afirst surface facing the first side of the vehicle frame and a secondsurface facing the second side of the vehicle frame with the first axlehousing coupled to the first surface and the second axle housing coupledto the second surface, and the gearbox being cantilevered outwardlyrelative to the aligned first and second axle housings to define agearbox axis parallel to the longitudinal axis and transverse to theaxle axis; and an electric motor coupled to the second surface of thegearbox and extending toward the first side of the vehicle frame todefine a motor axis with the motor axis being parallel to and offsetfrom the axle axis, parallel to the width-wise axis, transverse to thegearbox axis, and transverse to the longitudinal axis with the electricmotor coupled to the first and second drive shafts to rotate the firstand second wheel ends.

In another embodiment of the present disclosure, an axle assemblycomprises: a first axle housing having first and second housing ends; asecond axle housing having first and second axle housings; a first wheelend coupled to the first housing end of the first axle housing; a secondwheel end coupled to the first housing end of the second axle housing; afirst drive shaft at least partially housed within the first axlehousing and coupled to the first wheel end; a second drive shaft atleast partially housed within the second axle housing and coupled to thesecond wheel end; a gearbox having a body defining a perimeter with thebody having first and second portions defining a cavity with the firstaxle housing coupled to the first portion and the second axle housingcoupled to the second portion such that the first and second axlehousings extend in opposing directions, and the first and second axlehousings being aligned to define an axle axis, and the gearbox beingcantilevered relative to the aligned first and second axle housings todefine a gearbox axis transverse to the axle axis; and an electric motorcoupled to the first portion of the body adjacent the first axle housingand extending away from the first portion to define a motor axisparallel to and offset from the axle axis and transverse to the gearboxaxis; wherein the gearbox further includes a flange extending outwardlyfrom the perimeter of the body and a support rib directly coupling theflange to the body.

BRIEF DESCRIPTION OF THE DRAWINGS

Advantages of the present disclosure will be readily appreciated, as thesame becomes better understood by reference to the following detaileddescription, when considered in connection with the accompanyingdrawings. It is to be appreciated that the figures are merelyillustrative and are not necessarily drawn to scale. It is further to beappreciated that various features of the vehicle and/or the axleassembly are illustrated schematically in one or more of the figures atleast for purposes of simplifying the figure(s).

FIG. 1 is a semi-schematic side view of a portion of a vehicleillustrating a vehicle frame supporting a vehicle floor and a portion ofan embodiment of an axle assembly coupled to the vehicle frame.

FIG. 2 is a semi-schematic rear view of a portion of the vehicleillustrating the vehicle frame supporting the vehicle floor and the axleassembly of FIG. 1 coupled to the vehicle frame.

FIG. 3 is a perspective rear view of an embodiment of the axle assemblyillustrated in FIGS. 1 and 2, including suspension and steeringcomponents.

FIG. 4 is a perspective front view of the axle assembly illustrated inFIGS. 1 and 2.

FIG. 5 is a cross-sectional view of a portion of the axle assembly takenalong line 5-5 in FIG. 3.

FIG. 6 is an exploded view of a portion of the axle assembly of FIG. 4.

FIG. 7 is an exploded view of another portion of the axle assembly ofFIG. 4.

FIG. 8 is an exploded view of the portion of the axle assembly of FIG. 7shown at a different angle.

FIG. 9 is a perspective rear view of another embodiment of the axleassembly.

FIG. 10 is a partial exploded view of the axle assembly of FIG. 9.

FIG. 11 is a semi-schematic side view of a portion of a vehicleillustrating a vehicle frame supporting a vehicle floor and a portion ofanother embodiment of an axle assembly coupled to the vehicle frame.

FIG. 12 is a semi-schematic rear view of a portion of the vehicleillustrating the vehicle frame supporting the vehicle floor and the axleassembly of FIG. 11 coupled to the trailer frame.

FIG. 13 is a perspective front view of the axle assembly for the vehicleillustrated in FIGS. 11 and 12.

FIG. 14 is a top plan view of the axle assembly of FIG. 13.

FIG. 15 is a rear view of the axle assembly of FIG. 13.

FIG. 16 is a partial exploded view of the axle assembly of FIG. 13.

DETAILED DESCRIPTION

Referring now to the figures, wherein like numerals indicatecorresponding parts throughout the several views, various embodiments ofan axle assembly 100, 200 are shown throughout the figures and aredescribed in detail below. In certain embodiments, the axle assembly 100is a drive steer axle for any type of vehicle 10. In other embodiments,the axle assembly 200 is a rigid axle for any type of vehicle 10.Non-limiting examples of the vehicle 10 include a mass transit vehicle(such as a city bus, a commercial bus, a trolley vehicle, etc.), aschool bus, a commercial semi-truck and associated trailers, anagricultural vehicle, a passenger car or truck, and/or the like. If usedon a trailer, the trailer may be coupled to a semi-truck and may have aplurality of axle assemblies 200. In alternative embodiments, the axleassembly 100, 200 may also include a planetary, may be part of a tandemaxle, and/or may have a variety of additional features.

FIGS. 1 and 2 semi-schematically illustrate a portion of the vehicle 10including the axle assembly 100. The vehicle 10 includes a chassishaving a vehicle frame 12. The vehicle frame 12 has front 14 and rear 16ends and opposing first 18 and second 20 sides. The vehicle 10 furtherincludes a floor 22 coupled to the vehicle frame 12 and extendingbetween the front 14 and rear 16 ends to define a longitudinal axisA_(L) adapted to extend along a length of the vehicle 10. The floor 22further extends at least between the first 18 and second 20 sides todefine a width-wise axis A_(W) adapted to extend along a width of thevehicle 10. The vehicle frame 12 and the floor 22 are schematicallyillustrated in FIGS. 1 and 2, and the vehicle frame 12 may therefore belarger or smaller in the width-wise direction (i.e., along thewidth-wise axis A_(W)). Accordingly, the floor 22 may extend between thefirst 18 and second 20 sides of the vehicle frame 12 or beyond the first18 and second 20 sides of the vehicle frame 12.

The axle assembly 100 for the vehicle 10 is a steerable or steer driveaxle, and includes a first axle housing 102 and a second axle housing104, with each of the axle housings 102, 104 having first 106 and second108 housing ends. As shown in FIG. 2, the first housing end 106 of thefirst axle housing 102 extends toward the first side 18 of the vehicleframe 12, and the first housing end 106 of the second axle housing 104extends toward the second side 20 of the vehicle frame 12. The secondhousing ends 108 of the first 102 and second 104 axle housings arecoupled to a gearbox 110. The second housing ends 108 of the first 102and second 104 axle housings coupled to the gearbox 110 are shownschematically in the figures, as the first 102 and second 104 axlehousings can be coupled to the gearbox 110 in any suitable manner. In anembodiment, the first 102 and second 104 axle housings are mirror-imagesof one another. The axle housings 102, 104 may be made of or include anysuitable material.

The first 102 and second 104 axle housings are aligned to define an axleaxis A_(A) parallel to the width-wise axis A_(W). For example, and asshown, the axle assembly 100 further includes the gearbox 110 havingfirst 112 and second 114 surfaces with the first surface 112 facing thefirst side 18 of the vehicle frame 12 and the second surface 114 facingthe second side 20 of the vehicle frame 12. In other words, the first112 and second 114 surfaces oppose one another. The second housing ends108 of the first 102 and second 104 axle housings are coupled to thefirst 112 and second 114 surfaces, respectively, such that the secondends 108 of the first 102 and second 104 axle housings are aligned. Thefirst 102 and second 104 axle housings extend along the axle axis A_(A)in opposing directions. For example, the first axle housing 102 extendsalong a direction toward the first side 18 of the vehicle frame 12, andthe second axle housing 104 extends along the axle axis A_(A) in adirection toward the second side 104 of the vehicle frame 12.

Each of the first 102 and second 104 axle housings is a non-rotatinghousing; i.e., the axle housings 102, 104 do not rotate during operationof the vehicle 10. Accordingly, the first 102 and second 104 axlehousings are fixed to the gearbox 110 in any suitable manner, such aswith one or more fasteners or the like.

In an embodiment, and as shown in FIG. 3, the axle assembly 100 mayfurther include a stabilizing bar 115, with ends of the stabilizing bar115 coupled to the first 102 and second 104 axle housings via brackets117. The brackets 117 are configured to be coupled to a steering columnof the vehicle 10. Accordingly, the stabilizing bar 115 extends betweenthe brackets 117 and substantially parallel to the axle axis A_(A).

The axle assembly 100 further includes a first wheel end 116 coupled tothe first housing end 106 of the first axle housing 102 adjacent thefirst side 18 of the vehicle frame 12, and a second wheel end 118coupled to the first housing end 106 of the second axle housing 104adjacent the second side 20 of the vehicle frame 12. In an embodiment,the first 116 and second 118 wheel ends may be coupled to the secondhousing ends 108 by an articulated system. Each of the first 116 andsecond 118 wheel ends is coupled to at least one vehicle wheel or tire24. Each of the first 116 and second 118 wheel ends may also have aplurality of gears, such as a planetary gear set 120 including a gearratio. The transmission is given to the wheels 24 by a reduction insidethe respective steer wheel ends 116, 118, including the gear ratio.Utilizing power generated by an electric motor 122, the first 116 andsecond 118 wheel ends enable rotational motion of the wheel(s) 24 in aforward direction causing the vehicle 10 to move forwards or in abackward direction causing the vehicle 10 to move backwards. In anembodiment, each of the wheel ends 116, 118 may also include a dry diskbrake.

The axle assembly 110 further includes first 124 and second 126 driveshafts. The first drive shaft 124 is at least partially disposed withinthe first axle housing 102 and coupled to the first wheel end 116, andthe second drive shaft 126 is at least partially disposed within thesecond axle housing 104 and coupled to the second wheel end 118. Forexample, a portion of the first drive shaft 124 may be disposed throughthe first axle housing 102, and a remaining portion of the first driveshaft 124 may be disposed within the gearbox 110. Likewise, a portion ofthe second drive shaft 126 may be disposed through the second axlehousing 104, and a remaining portion of the second drive shaft 126 maybe disposed within the gearbox 110. As shown, each of the first 124 andsecond 126 drive shafts have first 128 and second 130 shaft ends. Eachof the first shaft ends 128 is coupled to a gear set 132 disposed withinthe gearbox 110, and each of the second shaft ends 130 is coupled to thefirst 116 and second 118 wheel ends, respectively. The drive shafts 124,126 deliver power (generated by the electric motor 122) from the gearset 132 in the gearbox 110 to the wheels 24 of the vehicle 10.Typically, the first 124 and second 126 drive shafts rotate within therespective first 102 and second 104 axle housings when powered oractivated by the electric motor 122 without engaging or otherwiserotating the axle housings 102, 104.

The first 124 and second 126 drive shafts can be any suitable drive orpropeller shaft. In an embodiment, each of the first 124 and second 126drive shafts is a cardan shaft. It is to be appreciated that the driveshafts 124, 126 can be any mechanical component that can suitablytransmit torque and rotation and/or deliver power to the wheels 24, andis not limited to a drive or propeller shaft.

In an embodiment, the axle assembly 100 further includes a differential134 disposed between the first 124 and second 126 drive shafts. Thedifferential 134 is coupled to the drive shafts 124, 126, and allowseach of the wheel ends 116, 118 to rotate at different speeds. Thisfacilitates handling of the vehicle 10, such as by enabling ease ofturning the vehicle 10. For instance, when the vehicle 10 is turning,the differential 134 allows the wheel(s) 24 coupled to the wheel end116, 118 at one side of the vehicle 10 to rotate faster than thewheel(s) 24 coupled to the other wheel end 116, 118 at the other side ofthe vehicle 10.

In an embodiment, the axle assembly 100 further includes first 136 andsecond 138 suspension components, which may be part of a suspensionsystem such as an air suspension system. The first suspension component136 coupled to the first axle housing 102 and the vehicle frame 12, andthe second suspension component 138 coupled to the second axle housing104 and the vehicle frame 12. In an embodiment, the first 136 and second138 suspension components are resiliently mounted to the vehicle frame12 through a spring, a damper, or other biasing component orarrangement. The suspension system stabilizes the vehicle, such as byallowing relative movement between the vehicle frame 12 and the vehiclewheels 24 as the vehicle 10 is moving. In this way, the suspensionsystem contributes to the handling and the ride quality of the vehicle10, as the suspension system provides the passengers with an even andsmooth ride despite driving over road bumps or potholes, etc.

As previously mentioned, the axle assembly 100 further includes thegearbox 110 that houses the plurality of gears 132 commonly referred toas a gear set or drive train. In an embodiment, the differential 134 isat least partially disposed within the gearbox 110. The gearbox 110 maybe centrally or substantially centrally located between the first 116and second 118 wheel ends. With this configuration, the gearbox 110forms a central portion of the axle assembly 100. It is to be understoodthat the gearbox 110 is schematically or semi-schematically shown in thefigures, and therefore certain features of the gearbox 110 are notshown.

The gearbox 110 has a body 140. The body 140 has the first surface 112facing the first side 18 of the vehicle frame 12 and the second surface114 facing the second side 20 of the vehicle frame 12. As shown, thefirst axle housing 102 is coupled to the first surface 112 of the body140, and the second axle housing 104 is coupled to the second surface114 of the body 140. In addition, the gearbox 110 is cantileveredoutwardly relative to the aligned first 102 and second 104 axle housingsto define a gearbox axis A_(G) parallel to the longitudinal axis A_(L)and transverse to the axle axis A_(A). The gearbox 110 is also spacedvertically downward from the floor 22 of the vehicle 10 along a verticalaxis A_(V) perpendicular to and intersecting both of the axle axis A_(A)and the gearbox axis A_(G).

In an embodiment, the body 140 of the gearbox 110 may have multipleportions. The multiple portions of the gearbox 110 may enable ease ofassembly and/or maintenance of the several components of the axleassembly 100, such as the assembly and/or maintenance of componentsinside the gearbox 110. In an embodiment, the body 140 may have first142 and second 144 portions with the portions 142, 144 defining a cavity146 for receiving the gear set 132. In the embodiment shown in FIGS.1-8, one of the portions 142, 144 of the body 140 may define the cavity146, while the other portion 142, 144 may define a cover 148 forcovering the cavity 146. It is contemplated that the body 140 of thegearbox 110 may have any suitable configuration, for example, the body140 could be a substantially single piece. It is also contemplated thatthe body 140 of the gearbox 110 can be made from any suitable material,not limited to metals and/or metal alloys. Further details of thegearbox 110 are described below.

The body 140 of the gearbox 110 may have any suitable shape. In anembodiment, the body 140 has an oblong shape, which may resemble an ovalshape or a rectangular shape with soft or rounded edges. In oneparticular embodiment, the body 140 has an oblong shape having a largersegment 150 (in terms of area and/or surface area) that blends into asmaller segment 152 (also in terms of area and/or surface area). Asshown, the first 102 and second 104 axle housings are coupled to thelarger segment 150 of the body 140, and the electric motor 122 iscoupled to the smaller segment 152 of the body 140.

In an embodiment, one of the first 142 and second 144 portions maydefine a base 154 and a continuous side wall 156 integrally coupled tothe base 154. As shown in FIG. 6, the first portion 142 defines the base154 with the continuous side wall 156. The base 154 and the side wall156 collectively define an interior surface 158 of the first portion142, with the interior surface 158 defining the cavity 146 for receivingand housing the gear set 132. The cavity 146 may have any suitable depthfor housing the gear set 132. The shape of the cavity 146 is notparticularly limited. In an embodiment, the shape of the cavity 146 maymimic or be similar to the general shape of the first portion 142 of thebody 140. Alternatively, the shape of the cavity 146 may differ from theshape of the first portion 142 of the body 140.

The continuous side wall 156 of the portion 142 also defines an exteriorsurface 160 of the body 140 of the gearbox 110. In an embodiment, thebody 140 has a plurality of corrugations 162, with the corrugations 162being formed in or on the exterior surface 160 of the body 140. Thecorrugations 162 may have any shape, such as a rounded shape (resemblingsemi-cylinders), a polygonal shape (resembling rectangles,semi-rectangles, triangles, semi-triangles, etc.), and/or combinationsthereof. Each corrugation 162 typically extends between the first 112and second 114 surfaces of the gearbox 110. In an embodiment, thecorrugations 162 are arranged adjacent one another with no spacingbetween the corrugations 162. Alternatively, the corrugations 162 may bespaced from one another. In an embodiment, the corrugations 162 arecontinuous along the entire exterior surface 160 of the body 140. Inanother embodiment, the corrugations 162 are discontinuous along theexterior surface 160 of the body 140. In this embodiment, corrugations162 may be present as a single corrugation 162 or a group ofcorrugations 162 in selected area(s) or region(s) of the exteriorsurface 160 of the body 140.

The corrugations 162 may have any size, at least in terms of the widthor diameter each corrugation 162. The corrugations 162 may also extendbetween the first 112 and second 114 surfaces of the gearbox (i.e.,along the entire the height of the side wall 156), or may extend alongpart of the distance between the first 112 and second 114 surfaces. Inaddition, the corrugations 162 formed in or on the exterior surface 160of the body 140 are substantially the same in terms of shape and size.Alternatively, the corrugations 162 may be different, where one or morecorrugations 162 may be different at least in terms of shape and sizefrom another corrugation(s) 162.

The body 140 of the gearbox 110 further has a perimeter 164, which isdefined by the exterior surface 160 of the body 140. In addition, thegearbox 110 has a flange 166 extending outwardly from the perimeter 164of the body 140. In an embodiment, the flange 166 extends from theperimeter 164 of the body 140, with the flange 166 having a largersurface area adjacent the smaller segment 152 of the body 140 and asmaller surface area adjacent the larger segment 150 of the body 140. Inan alternative embodiment, the flange 166 extends from the perimeter 164of the body 140 only along the smaller segment 152 of the body 140. Theflange 166, which has the larger surface area, adjacent the smallerportion 152 of the body 140 provides additional strength to the gearbox110 so that the gearbox 110 can suitably hold and/or support theelectric motor 122 cantilevered from the gearbox 110. In an embodiment,the flange 166 adjacent the smaller segment 152 of the body 140 incombination with the corrugations 162 defined in or on the exteriorsurface 160 of the body 140 provides additional strength to the gearbox110 so that the gearbox 110 can suitably hold and/or support theelectric motor 122 cantilevered from the gearbox 110.

As shown, the flange 166 has first 168 and second 170 opposing flangesurfaces, with the first flange surface 168 of the flange 166 adjacentto the corrugations 162 formed in or on the side wall 156 of the body140. The second flange surface 170 of the flange 166 provides a couplingsurface of the electric motor 122, and when assembled, the second flangesurface 170 of the flange 166 is adjacent to the electric motor 122. Theflange 166 may be made of or includes any suitable material, not limitedto metals and metal alloys. In an embodiment, the flange 166 is made ofor includes the same material as the body 140 of the gearbox 110.

The gearbox 110 further has a support rib 172 directly coupling theflange 166 to the body 140. In another embodiment, the gearbox 110further has a plurality of support ribs 172 with each support rib 172directly coupling the flange 166 to the body 140. Each of the supportrib(s) 172 may have any suitable shape and size, and is typically largerthan a corrugation 162 in terms of width (for example, an effectivediameter of the rib 172). The support rib(s) 172 may extend between thefirst 112 and second 114 surfaces of the gearbox 110 (i.e., along theentire height of the side wall 156 of the body 140). Alternatively, thesupport rib(s) 172 may extend along part of the distance between thefirst 112 and second 114 surfaces of the gearbox 110.

The support rib(s) 172 may have a rounded shape, a polygonal shape,and/or combinations thereof. In one embodiment, one or more of thesupport ribs 172 has a tapered surface with a non-tapered end 174adjacent the flange 166 and a tapered end 176 adjacent the secondportion 144 of the body 140. The support ribs 172 may be substantiallythe same in terms of shape and size, or may be different. If different,one of the support ribs 172 may be different at least in terms of shapeand size from another support rib 172. In addition, the support ribs 172may be distributed in selected positions along a portion of theperimeter 164 of the body 160. In an alternative embodiment, the supportribs 172 are distributed in selected positions along the entireperimeter 164 of the body 160.

As mentioned above, the axle assembly 100 further includes the electricmotor 122. While the term electric motor 122 is used, the motor 122 doesnot have to be electric and can instead be any suitable type of motor.It is to be understood that the electric motor 122 is schematically orsemi-schematically shown in the figures, and therefore certain featuresof the electric motor 122 (such as the internal components of the motor122) are not shown.

The electric motor 122 is coupled to the first 124 and second 126 driveshafts to rotate the first 116 and second 118 wheel ends. In addition,the electric motor 122 is directly coupled to the gearbox 110. Theelectric motor 122 may be directly coupled to the gearbox 110 in anysuitable manner, such as with one or more fasteners. As shown, theelectric motor 122 may have a casing 178 with an outer surface 179 andmay have a generally cylindrical shape. The electric motor 122 furtherhas internal motor components disposed within the casing 178, which arenot shown. The electric motor 122 may also have a flange 180 extendingoutwards from the casing 178. When assembled, the flange 180 of thecasing 178 aligns with and is coupled to the flange 166 of the gearbox110 in any suitable manner, such as with one or more fasteners.

The electric motor 122 is also coupled to the gearbox 110 by a gear set132 disposed within the cavity 146 of the gearbox 110. In an embodiment,the axle assembly 100 has a plurality of gears 181 making up the gearset 132. In one example, the gear set 132 has three gears 131, with oneof the gears 181 being a pinion gear that directly couples to theelectric motor 122 via an output shaft 183, another of the gears 181being part of the differential 134, and another of the gears 181 beingan idler gear disposed between the pinion and differential gears. Thegears 181 are also typically disposed parallel to the axle axis A_(A)and parallel to the width-wise axis A_(W). The gears 181 are configuredto translate energy generated by the electric motor 122 into movement ofthe drive shafts 124, 126. For example, the gears 181 may be configuredto convert linear motion of the electric motor 122 into rotationalmotion of the drive shafts 124, 126 which effects rotational movement ofthe vehicle wheels 24.

In another embodiment, and as shown in FIGS. 9 and 10, the axle assembly100 includes a motor housing 194 integrally coupled to the flange 166 ofthe gearbox 110 with the electric motor 122 disposed within the motorhousing 194. In the embodiment shown, the motor housing 194 has a body196 and a removable cap 198. When the cap 198 is removed, the electricmotor 122 is placed within the body 196 of the motor housing 194. Thecap 198 is then secured to the body 196 to enclose the electric motor122 within the motor housing 194. The body 196 of the motor housing 194may have any suitable shape and size. In an embodiment, the body 196 hassubstantially the same general shape as the electric motor 122; however,the body 196 may be slightly larger than the electric motor 122 so thatthe electric motor 122 can easily fit within the body 196. The motorhousing 194 may also be made of or include any suitable strong materialsuch as, but not limited to, metals and/or metal alloys.

In an embodiment, the electric motor 122 (or motor housing 194), whichis coupled to the second surface 114 of the gearbox 110 and, moreparticularly, to the second surface 170 of the flange 166 of the gearbox110, extends toward the first side 18 of the vehicle frame 12 to definea motor axis A_(M). The motor axis A_(M) is parallel to and offset fromthe axle axis A_(A), and is parallel to the width-wise axis A_(W). Inaddition, the motor axis A_(M) is transverse to the gearbox axis A_(G),and is transverse to the longitudinal axis A_(L), and the motor axisA_(M) is also perpendicular to the vertical axis A_(V) and the gearboxaxis A_(G). Accordingly, and as shown, the electric motor 122 (or motorhousing 194 that houses the electric motor 122) is cantilevered from thegearbox 110.

As being cantilevered, the electric motor 122 (or motor housing 194) iscoupled to the flange 166 of the gearbox 110, and is not coupled to thefirst axle housing 102. Accordingly, the outer surface 179 of theelectric motor 122 (or the motor housing 194) is spaced from the firstaxle housing 102 and/or vehicle frame 12. In addition, the electricmotor 122 (or motor housing 194) is spaced vertically downwardly fromthe floor 22 of the vehicle 10 and spaced from the vehicle frame 12.

In operation, the electric motor 122 provides power to the gearbox 110using the internal gears 181 of the gear set 132, which transmit thepower through the differential 134 and to the first 124 and second 126drive shafts. The drive shaft 124 receives the power and rotates withinthe first axle housing 102 to effect rotation of the first wheel end116. Likewise, the drive shaft 126 receives the power and rotates withinthe second axle housing 104 to effect rotation of the second wheel end118. The wheel ends 116, 118, in turn, rotate and propel the wheels 24of the vehicle 10.

Another embodiment of the axle assembly 200 is described below withreference to FIGS. 11-16. This embodiment of the axle assembly 200 is arigid axle that may be used for a vehicle 10, such as a trailer pulledby a semi-truck. As shown in FIGS. 11 and 12, the vehicle or trailer 10includes a chassis having the vehicle frame 12. The vehicle frame 12 hasthe front 14 and rear 16 ends and opposing first 18 and second 20 sides.The vehicle or trailer 10 further includes a floor 22 coupled to theframe 12 and extending between the front 14 and rear 16 ends to definethe longitudinal axis A_(L) adapted to extend along the length of thevehicle or trailer 10. The floor 22 further extends between the first 18and second 20 sides to define the width-wise axis A_(W) adapted toextend along the width of the vehicle or trailer 10.

The axle assembly 200 of the present embodiment is a rigid axle. Theaxle assembly 200 has many of the same components as the axle assembly100, including the first 102 and second 104 axle housings, the first 124and second 126 drive shafts disposed at least partially within therespective first 102 and second 104 axle housings, and the electricmotor 122. Details of each of these components are described above forthe axle assembly 100 and shown in one or more of FIGS. 1-8. At leastfor purposes of simplifying the figures. It is noted that variousfeatures of the electric motor 122 and gearbox 210 of the presentembodiment are shown schematically or semi-schematically in FIGS. 11-16.

The axle assembly further includes first 216 and second 218 wheel ends,with the first wheel end 216 coupled first housing end 106 of the firstaxle housing 102 and the second wheel end 218 coupled to the firsthousing end 106 of the second axle housing 102. In the presentembodiment, the first 216 and second 218 wheel ends do not articulate asthe axle assembly 200 is a rigid axle. In addition, each of the first216 and second 218 wheel ends may or may not include any gears or a gearreduction.

The axle assembly 200 further includes the gearbox 210 having a body240. The body 240 has a first surface 212 facing the first side 18 ofthe frame 12 and a second surface 214 facing the second side 20 of theframe 12. As shown, the first axle housing 102 is coupled to the firstsurface 212 of the body 240, and the second axle housing 104 is coupledto the second surface 214 of the body 240. In addition, the gearbox 210is cantilevered outwardly relative to the aligned first 102 and second104 axle housings to define the gearbox axis A_(G) parallel to thelongitudinal axis A_(L) and transverse to the axle axis A_(A). Thegearbox 210 is also spaced vertically downward from the floor 22 of thevehicle or trailer 10 along the vertical axis A_(V) perpendicular to andintersecting both of the axle axis A_(A) and the gearbox axis A_(G).

The body 240 of the gearbox 210 has multiple portions. In thisembodiment, the body 240 has a first portion 242 and a second portion244. As shown in FIG. 16, the first 242 and second 244 portions aresubstantially equal to define a cavity 246 for receiving a gear set (notshown). In an embodiment, the cavity 246 receives a gear set similar tothe gear set 132 described above. Each of the first 242 and second 244portions of the body 140 defines the cavity 246, where part of thecavity 246 is defined in the first portion 242 and the another part ofthe cavity 246 is defined in the second portion 244. It is contemplatedthat the body 240 of the gearbox 210 can be made from any suitablematerial, not limited to metals and/or metal alloys.

The body 240 of the gearbox 210 may have any suitable shape. In anembodiment, the body 240 has an oblong shape, which may resemble an ovalshape or a rectangular shape with soft or rounded edges. In addition,each of the first 242 and second 244 portions of the body 240 define aside wall 256 having an interior surface 258. The interior surfaces 258of the first 242 and second 244 portions collectively define the cavity246 for receiving the gear set. The cavity 246 may have any suitablesize/depth for housing the gear set. The shape of the cavity 246 is alsonot particularly limited.

The side walls 256 of the first 242 and second 244 portions define anexterior surface 260 of the body 240 of the gearbox 210. In anembodiment, the body 240 has a plurality of body ribs 263, with the bodyribs 263 being formed on the exterior surface 260 of the body 240. Inparticular, the body ribs 263 are formed on the side walls 256 of boththe first 242 and second 244 portions of the body 240. The body ribs 263may have any shape, such a wedge shape as shown. Alternatively, the bodyribs 263 may have a rounded shape, a polygonal shape, and/orcombinations thereof. The body ribs 263 are spaced from one another, andare distributed along the entire side wall 256 of each of the portions242, 244. In an embodiment, a body rib 263 formed on the side wall 256of the first portion 242 is aligned with a body rib 263 formed on theside wall 256 of the second portion 244.

The body ribs 263 may have any size, at least in terms of the widthdefined across each body rib 263. Each body rib 263 may extend entirelyor partially along the height of the side wall 256 of each of theportions 242, 244. In one embodiment, and as shown, the body ribs 263extend along the entire height of the side wall 256 of the first portion242, while the body ribs 263 extend partially along the height of theside wall 256 of the second portion 244. In addition, the body ribs 263may be substantially the same in terms of shape and size. Alternatively,the body ribs 263 may be different, where one or more body ribs 263 maybe different at least in terms of shape and size from another body rib263.

Each of the first 242 and second 244 portions of the body 240 has aperimeter 264, which is defined by the exterior surface 260 of theportions 242, 244. In addition, each of the portions 242, 244 has a lip265, and the lips 265 are aligned for coupling the first portion 242with the second portion 244 such as, for example, with a plurality offasteners.

The first portion 242 of the body 240 further has a flange 266 extendingoutwardly from the perimeter 264 of the first portion 242. In anembodiment, the flange 266 has a larger surface area than the firstportion 242 and provides additional strength to the gearbox 210 so thatthe gearbox 210 can suitable hold and/or support the electric motor 122that is cantilevered from the gearbox 210. In an embodiment, the flange266 in combination with the body ribs 263 on the side walls 256 of thefirst 242 and second 244 portions of the body 240 provides additionalstrength to the gearbox 210 so that the gearbox 210 can suitably holdand/or support the electric motor 122 that is cantilevered from thegearbox 210.

As shown, the flange 266 has first 268 and second 270 opposing flangesurfaces, with the first flange surface 268 of the flange 266 adjacentto the body ribs 263 on the side wall 256 of first portion 242 of thebody 140. The second flange surface 270 of the flange 266 provides acoupling surface for the electric motor 122, and when assembled, thesecond flange surface 270 of the flange 266 is adjacent to the electricmotor 122. The flange 266 may be made of or includes any suitablematerial, not limited to metals and metal alloys. In an embodiment, theflange 266 is made of or includes the same material as the body 240 ofthe gearbox 210.

The gearbox 210 further has a support rib 272 directly coupling theflange 266 to the body 240. In another embodiment, the gearbox 210further has a plurality of support ribs 272 with each support rib 272directly coupling the flange 266 to the body 240. Each of the supportrib(s) 272 may have any suitable shape and size, and is typically largerthan one of the body ribs 263. The support rib(s) 272 may extend alongthe entire height of the side wall 256 of the first portion 242 of thebody 240.

The support rib(s) 272 may have any suitable shape. In an embodiment,and as shown, the support ribs 272 have a wedge shape, with the largerend of the wedge adjacent the flange 266. The support ribs 272 may besubstantially the same in terms of shape and size, or may be different.If different, one of the support ribs 272 may be different at least interms of shape and size from another support rib 272. In addition, thesupport ribs 272 may be distributed in selected positions along aportion of the perimeter 264 of the body 260.

Various embodiments of the axle assembly 100, 200 have been described indetail above. These embodiments overcome challenges associated witheffectively attaching the electric motor to the gearbox of the axleassembly within limited available space under the vehicle floor. Forexample, a challenge with having an electric motor extending from thegearbox toward one of the sides of the vehicle frame, such that theelectric motor is parallel with the drive shaft, is that the electricmotor could experience an undesirable bending moment. This bendingmoment may be caused, at least in part, from several g-forceaccelerations experienced by the electric motor in a vertical directionwhen the vehicle is traveling over blemishes in the road. The bendingmoment may also be caused, at least in part, from vibrations generatedby internal rotating components of the electric motor. The axleassemblies 100, 200 of the present disclosure overcome this challenge byproviding a structurally superior gearbox 110, 210 that can transmit theload experienced by the axle assembly 100, 200 (for example, from theweight of the vehicle 10 and the passenger(s)/cargo inside the vehicle10) to the first 102 and second 104 axle housings. The axle assembly100, 200 can support more than ten g-force accelerations experienced bythe electric motor 122.

In addition, the arrangement of the electric motor 122 relative to thegearbox 110, 210 is such that the electric motor 122 is positionedadjacent the first axle housing 102, and not above the first axlehousing 102. In this way, the electric motor 122 does not occupy spacebetween the frame 12, 32 and the axle assembly 100, 200. When used as amass transit vehicle, such as a commercial bus, the spatial arrangementor position of the electric motor 122 provides the necessary clearancebetween the axle assembly 100 and the vehicle floor 22. Accordingly, theaxle assembly 100 does not restrict the travel distance of thesuspension components 136, 138, which could otherwise adversely affecthandling and the overall ride quality of the vehicle 10. In addition,with good clearance, the floor 22 of the vehicle 10 can be positionedcloser to the ground, which increases the space within the passengercompartment of the vehicle 10.

While the invention has been described with reference to the examplesabove, it will be understood by those skilled in the art that variouschanges may be made and equivalents may be substituted for elementsthereof without departing from the scope of the invention. In addition,many modifications may be made to adapt a particular situation ormaterial to the teachings of the invention without departing from theessential scope thereof. Therefore, it is intended that the inventionnot be limited to the particular embodiment disclosed as the best modecontemplated for carrying out this invention, but that the inventionwill include all examples falling within the scope of the appendedclaims.

What is claimed is:
 1. A vehicle comprising: a vehicle frame havingfront and rear ends and opposing first and second sides; a floor coupledto said vehicle frame and extending between said front and rear ends todefine a longitudinal axis adapted to extend along a length of thevehicle, and said floor further extending at least between said firstand second sides to define a width-wise axis adapted to extend along awidth of the vehicle; a first axle housing and a second axle housingeach having first and second housing ends with said first housing end ofsaid first axle housing extending toward said first side of said vehicleframe and said first housing end of said second axle housing extendingtoward said second side of said vehicle frame, and said first and secondaxle housings being aligned to define an axle axis parallel to saidwidth-wise axis; a first wheel end coupled to said first housing end ofsaid first axle housing adjacent said first side of said vehicle frame;a second wheel end coupled to said first housing end of said second axlehousing adjacent said second side of said vehicle frame; a first driveshaft at least partially disposed within said first axle housing andcoupled to said first wheel end; a second drive shaft at least partiallydisposed within said second axle housing and coupled to said secondwheel end; a gearbox having a body with said body having a first surfacefacing said first side of said vehicle frame and a second surface facingsaid second side of said vehicle frame with said first axle housingcoupled to said first surface and said second axle housing coupled tosaid second surface, and said gearbox being spaced apart from saidvehicle frame and cantilevered outwardly relative to said aligned firstand second axle housings to define a gearbox axis parallel to saidlongitudinal axis and transverse to said axle axis, said first andsecond axle housings coupled to said vehicle frame to support saidgearbox for movement relative to said vehicle frame with said first andsecond axle housings; an electric motor coupled to said first surface ofsaid gearbox to support said electric motor for movement relative tosaid vehicle frame with said gearbox, said electric motor extendingtoward said first side of said vehicle frame to define a motor axis withsaid motor axis being parallel to and offset from said axle axis,parallel to said width-wise axis, transverse to said gearbox axis, andtransverse to said longitudinal axis with said electric motor coupled tosaid first and second drive shafts to rotate said first and second wheelends; and a plurality of gears disposed within said gearbox; whereinsaid body of said gearbox comprises a base and a cover, wherein saidbase defines a cavity and said cover coupled to said base and coveringsaid cavity, wherein said plurality of gears are disposed within saidcavity of said base, and wherein said base includes said first surfaceof said body that is coupled to said first axle housing and wherein saidcover includes said second surface of said body that is coupled to saidsecond axle housing; wherein said gearbox is spaced vertically downwardfrom said floor along a vertical axis perpendicular to and intersectingboth of said axle and gearbox axes, wherein the gearbox axis extendslongitudinally and parallel to the longitudinal axis; and wherein saidelectric motor is spaced vertically downward from said floor with saidmotor axis being perpendicular to said vertical axis and said gearboxaxis; wherein said body of said gearbox has a perimeter and said gearboxfurther has a flange extending outwardly from said perimeter of saidbody adjacent to said electric motor, and wherein said body has asupport rib directly coupling said flange to said body, wherein thesupport rib extends from said first surface of said body to said secondsurface of said body, and wherein the support rib comprises a taperedsurface with a non-tapered end adjacent to the flange and a tapered endadjacent to said second surface of said body.
 2. The vehicle as setforth in claim 1 wherein said body has a plurality of support ribs witheach support rib directly coupling said flange to said body.
 3. Thevehicle as set forth in claim 1 wherein said body of said gearbox has atleast one of a plurality of corrugations and a plurality of body ribs.4. The vehicle as set forth in claim 1 wherein said electric motor iscantilevered from said gearbox.
 5. The vehicle as set for in claim 1wherein said electric motor has an outer surface with said outer surfacebeing spaced from said first axle housing.
 6. The vehicle as set forthin claim 1 wherein said electric motor is directly coupled to saidflange of said gearbox.
 7. The vehicle as set forth in claim 1 furthercomprising a motor housing coupled to said flange of said gearbox withsaid electric motor disposed within said motor housing.
 8. The vehicleas set forth in claim 1 further comprising a differential for couplingsaid electric motor to said first and second wheel ends.
 9. The vehicleas set forth in claim 1 wherein each of said first and second wheel endshas a planetary gear set.
 10. An axle assembly comprising: a first axlehousing having first and second housing ends; a second axle housinghaving first and second housing ends; a first wheel end coupled to saidfirst housing end of said first axle housing; a second wheel end coupledto said first housing end of said second axle housing; a first driveshaft at least partially housed within said first axle housing andcoupled to said first wheel end; a second drive shaft at least partiallyhoused within said second axle housing and coupled to said second wheelend; a gearbox having a body defining a perimeter with said body havingfirst and second portions defining a cavity with said first axle housingcoupled to said first portion and said second axle housing coupled tosaid second portion such that said first and second axle housings extendin opposing directions, and said first and second axle housings beingaligned to define an axle axis, and said gearbox being cantileveredrelative to said aligned first and second axle housings to define agearbox axis transverse to said axle axis; an electric motor coupled tosaid first portion of said body adjacent said first axle housing andextending away from said first portion to define a motor axis parallelto and offset from said axle axis and transverse to said gearbox axis;and a plurality of gears disposed within said gearbox; wherein saidgearbox further includes a flange extending outwardly from saidperimeter of said body with said electric motor coupled to said flange,and said gearbox further having a support rib directly coupling saidflange to said body said first and second axle housings are configuredto be coupled to a vehicle frame to support said gearbox for movementrelative to said vehicle frame with said first and second axle housings,and said gearbox is configured to support said electric motor formovement relative to said vehicle frame with said gearbox; wherein saidfirst portion of said body of said gearbox comprises a base that definessaid cavity, wherein said second portion of said body of said gearboxcomprises a cover coupled to said base and covering said cavity, andwherein said plurality of gears are disposed within said cavity of saidbase, and wherein said base includes said first surface of said bodythat is coupled to said first axle housing and wherein said coverincludes said second surface of said body that is coupled to said secondaxle housing; wherein said gearbox is configured to be spaced verticallydownward from said vehicle frame along a vertical axis perpendicular toand intersecting both of said axle and gearbox axes, wherein the gearboxaxis extends longitudinally and parallel to a longitudinal axis of saidvehicle frame; and wherein said electric motor is configured to bespaced vertically downward from said vehicle frame with said motor axisbeing perpendicular to said vertical axis and said gearbox axis; whereinthe support rib extends from said first surface of said body to saidsecond surface of said body, and wherein the support rib comprises atapered surface with a non-tapered end adjacent to the flange and atapered end adjacent to said second surface of said body.
 11. The axleassembly as set forth in claim 10 wherein said body has a plurality ofsupport ribs with each support rib directly coupling said flange to saidbody.
 12. The axle assembly as set forth in claim 11 further comprisinga motor housing coupled to said flange of said gearbox with saidelectric motor disposed within said motor housing.
 13. The axle assemblyas set forth in claim 10 wherein said body of said gearbox has at leastone of a plurality of corrugations and a plurality of body ribs.
 14. Theaxle assembly as set forth in claim 10 wherein said electric motor iscantilevered from said gearbox.
 15. The axle assembly as set forth inclaim 10 wherein said electric motor has an outer surface with saidouter surface being spaced from said first axle housing.
 16. The axleassembly as set forth in claim 10 further comprising a differentialincluding one of said gears for coupling said electric motor to saidfirst and second drive shafts.